The present invention relates to an image display prepared from a color photograph or LCD display so as to present a three-dimensional effect to the observer. The invention also relates to a method for enhancing the display of certain color photocopies.
Paralleling the development and acceptance of photography has been a desire to present images that appear lifelike, that is, three-dimensional. Various techniques have been conceived for creating a three-dimensional (3D) effect. Stereograms were produced by taking two photographs of the same field of view from the perspective of separate human eyes, and then displaying them separately to the eyes of the observer using a special apparatus. Holograms display impressive three-dimensional images, but a laser must be used to create the hologram.
Three-dimensional effects in motion pictures and television have also relied on complex techniques for recording and viewing the subject. The audience must wear special glasses to xe2x80x9cdecodexe2x80x9d the special images and trick the brain into xe2x80x9cseeingxe2x80x9d three dimensions.
Photographic prints taken with a single lens camera present a two-dimensional image. It has been generally believed that one cannot make a hologram from a photographic print. Some contrast enhancement of black and white photographs has been obtained using the well-known process of unsharp masking, but no process is known for displaying normal color photographic prints (traditional or digital) with a three-dimensional effect. Nor is there a known process for displaying digital photographs with a three-dimensional effect.
In some commercial sales efforts, salespersons provide color photocopies of photographs to potential customers. For example, real estate agents often use color photocopies to show properties to prospects. However, non-enhanced color photocopies may not be as lifelike as the salesperson desires.
Thus, there is a need for a straightforward, inexpensive process for creating a three-dimensional effect in viewing photographs and moving images, and a further need for enhancing color photocopies of photographs.
The present invention seeks to provide an image display with a three-dimensional effect, prepared from a color analog or digital photograph, or from a digital display screen.
This object is achieved in the present invention by superimposing color raster-pixel representations of the same field of view.
Generally described, the present invention provides an image display, comprising: a first color raster-pixel representation of a three-dimensional field of view, including depth information, presented on a two-dimensional base medium; and a second color raster-pixel representation of the three-dimensional field of view, including depth information, presented on a two-dimensional transparent cover medium; and being held in spaced apart, aligned relation to one another. A person looking at the image display from the side of the second representation perceives a three-dimensional effect.
Such an image display may be prepared, according to one embodiment of the invention, from a color photographic print, by making a color photocopy of the print on translucent paper, and then making another photocopy of the print on a transparency. The two photocopies are assembled so that the raster-pixel representations are aligned and spaced from one another. Alternatively, the image display may be prepared, according to another embodiment of the invention, from a color digital photograph. The image file is printed first on paper, and then on a transparency, using a color photocopier or a color laser printer. The representations differ in at least one optical characteristic, which may result, for example, from differences in the media on which they are presented or different parameters used in their creation.
In both of the foregoing embodiments, the two representations preferably are spaced from about 0.03 to about 0.07 inch. This spacing may be provided by the thickness of the transparency or by one or more spacers, preferably a layer of Lexan plastic and two layers of Mylar plastic between the Lexan and the paper photocopy. The three-dimensional effect is maximized by simultaneously back-lighting the paper photocopy to pass light through the translucent paper base medium and front lighting to direct light through the transparent cover medium while also illuminating the transparency.
In still another embodiment of the invention, an image display with a three-dimensional effect is prepared by superimposing two LCD displays of the same field of view. This embodiment provides three-dimensional moving images.
The present invention also provides a method of preparing an image display, comprising: inputting to a laser printing device a color image including depth information; printing a first raster-pixel representation of the color image on a base medium; printing a second raster-pixel representation of the color image on a transparent cover medium; aligning the representations and mounting them in spaced apart relation. The laser printing device may be, for example, a color photocopier or a color laser printer. In one embodiment, the inputting step comprises mounting a color photographic print in a frame including registration indicia, and exposing the mounted print in a color photocopier, such that the registration indicia appear on both of the representations; and wherein the aligning step comprises aligning the registration indicia. In another embodiment, the inputting step comprises sending a file containing a digital photographic image to a color laser printer or photocopier.
Output from color digital cameras produces a somewhat more enhanced 3D effect than that produced from color print analog cameras. This is believed due to a xe2x80x9cpixel multiplication effectxe2x80x9d when the color digital camera output is processed by the analog to digital color copier. Holographic phase data is believed to be recovered and displayed via raster/pixel refraction. Pixel multiplication recovers and displays more of the phase data encoded in the photographed image. A drawback to the digital camera is a slight grain to the image due to pixel multiplication.
It will therefore be understood that the present invention provides an improved method for displaying color photocopies of photographs.
Color photographic prints, unlike black and white prints, have multiple layers of photographic emulsions to record the three complementary colors that combine to represent the colors in the field of view. In one of its aspects, the present invention relates to the extraction, magnification and display of optical intensity and holographic phase data from a conventional color photograph with a color analog to digital color copying device to create the visual sensation of a 3D image to a human observer. It is believed that holographic phase and optical intensity data recovery, multiplication, and display are accomplished by optical interaction with raster and pixel patterns at the discontinuity between a translucent and transparent full color raster/pixel format copy of the original color photograph. The translucent and transparent copies of the color photograph are optically slightly dissimilar from each other, as produced by an analog to digital color copying device. The 3D image generated by this effect has characteristics of both a color hologram and a color auto stereogram and is believed to represent a hybrid between these two types of 3D images. The 3D image created by this effect has the characteristic of being sensed immediately by an observer and then gaining in strength as the observer gazes at the image. Most observers report that maximum 3D effect is reached after the observer""s brain has fully assimilated the 3D image, a process taking about 60 seconds.
Referring in more detail to creating 3D effect image displays from color photographs, the first copy of the color photograph is rendered by an analog to digital color copying device in four color raster/pixel format on translucent paper with maximum sharpness and contrast and exposure set at mid level intensity. Specific analog to digital color copying devices may require additional special settings unique to that device. This first copy is called the base element. The second copy of the color photograph is rendered by the same analog to digital color copying device in four color raster pixel format on a transparent medium with minimum sharpness, contrast and with the exposure set at maximum light intensity. This second, transparent copy, is called the cover element. The cover element is placed over the front surface of the base element and, after alignment to null out moire interference patterns created by the interacting raster/pixel patterns, is physically locked into place. The cover element is then separated from the base element, in a direction perpendicular to the front surface of the base element, by multiple layers of transparent material, preferably with a thickness of 0.005 to 0.010 inches, and a refractive index slightly different from that of the transparent cover element. These layers are termed separation elements or spacers. Slight air gaps may be allowed to exist between the cover element and the top separation element, between separation elements and between the bottom separation element and the base element. The total separation between the base element and the cover element preferably is held to between 0.005 to 0.070 inches. The actual separation distance may be adjusted for maximum 3D effect.
White light, at a color temperature of 5000 degrees Kelvin, projected through the translucent base element of the assembled image display and incident white light passing through the cover element to reflect from the surface of the base element, optically interact with the two sets of color raster and pixel patterns; they also optically interact with the discontinuities between the base and cover elements and with the discontinuities between the separation elements to create intensity and phase interference patterns. These interference patterns are believed to represent the extracted and magnified holographic phase data and intensity data that is encoded within the color photograph. Light refracted and scattered by these intensity and phase interference patterns over the entire area of the composite page creates the sensation of a 3D image to a human observer. The image displayed is a duplicate of the 3D image which was present at the film plane in the camera which captured the original photograph. Projecting white light through the rear of the base element of the image display has the additional effect of canceling some of the multiplied intensity information. The resulting presentation appears very close to the actual light intensity level present when the photograph was captured by the camera.
While the theory of what produces the 3D effect of the present invention is not fully understood, the explanation found above is believed likely to be accurate. The following corollaries are also believed to be true:
Corollary 1
Encoded within every color photograph is holographic phase and intensity information which represents the 3D nature of the subject being photographed. It is believed that this holographic data is recorded within the pictorial elements of the photograph.
Corollary 2
Each time a photographic print is copied photographically, a small amount of the holographic phase and intensity data is lost. The best presentation of holographic phase and intensity information from a color photograph, when using the present invention, is obtained from the first generation color photographic print of a color print negative.
Corollary 3
The strength of the 3D effect in the image display with a spacing between elements of, for example, 0.005 inches is inversely proportional to the real size of the object photographed, that is, an image display of a color photomicrograph will yield a more pronounced 3D effect than will an image display created from a color photograph of a large subject.
Corollary 4
The strength of the 3D effect is directly related to the level of contrast and image sharpness in the original color photograph from which the image display was created.
Corollary 5
Increasing the spacing between the base element and cover element with additional spacing elements increases the strength of the 3D effect. However, little increase in the strength of the 3D effect is obtained with spacing beyond 0.070 inches.
Corollary 6
The 3D Effect does not operate with images which contain no holographic phase data. These images include the following broad types:
a. black and white photographs,
b. dot screen black and white or color images such as those in a magazine or newspaper,
c. perspective color or black and white line drawings,
d. printed continuous tone color images,
e. computer generated color images.
Corollary 7
Producing a image display according the invention from another such image display results in the deterioration of the 3D effect the second image display with a corresponding loss of image quality and resolution.
Corollary 8
Producing a composite base element and composite cover element from transparent four color overlays produces the same 3D effect as using a single translucent base element and transparent cover element.
Corollary 9
A image display made up of a composite four color transparent overlay base element and a single four color transparent cover element produces the same 3D effect as an image display made of a single four color translucent base element and a four color transparent cover element.
Corollary 10
An image display made up of a single translucent four color base element and a composite four color transparent overlay cover element produces the same 3D effect as an image display made of a single translucent four color base element and composite transparent four color cover element.
Corollary 11
The higher the resolution, expressed in DPI (Dots Per Inch), of the analog to digital color copying device used in the creation of an image display, the higher the image quality of that image display.
Corollary 12
The invention is effective with Polaroid(trademark) color photographs with some slight reduction in the strength of the 3D effect in the resulting image display as compared to an image display produced from conventional color photographs of the same subject.
Corollary 13
Enlarging a color photograph with the analog to digital color copying device when creating the image display enlarges the 3D effect by a proportional amount.
Corollary 14
Producing an image display of a color photograph of an image display presents a magnified 3D effect in the second generation image display with a corresponding loss of image resolution.
Other objects, features and advantages of the present invention will be apparent upon reading the following detailed description of preferred embodiments of the invention, when taken in conjunction with the drawings and the appended claims.